Refrigeration apparatus



E. T. WILLIAMS REFRIGERATION APPARATUS 5 3 9 l om 2 Original Filed Nov. 27, 1929 2 Sheets-Sheet l INVENTOR ATTORN y 1935- E. T, WILLIAMS Re. 19,595

REFRGERATION APPARATUS Original Filed Nov 27, 1929 2 Sheets-Sheet 2 ATTORNEY INVENTOR Java/J WM Reiscued May 28, 1935 Edward T. Williams,

7/ Original No. 1,947,574, dated February 20, 1934,

Serial No. 410,026, November 27, 1929. cation for reissue November 19, 1934, Serial No.

My invention relates to the art of refrigeration and particularly to refrigerating apparatus of the so-called compression type and still more particularly to compression refrigerating apparatus when used in connection with multiple installations.

This type ofinstallation is used particularly in apartment houses where a refrigerator cabinet containing an evaporator is placed in each of a plurality of apartments and supplied with refrigerant from a single compressor and condenser. It is customary to place as many as thirty evaporators in a single system and hence the quantity of refrigerant contained in such a system is necessarily large. In systems used heretofore, if a leak occurred in one apartment, the entire contents of the system was free to escape through this leak, and this large quantity a smaller quantity of refrigerant for a given numberpf evaporators than has heretofore been found possible. Another-object is to provide safety devices whereby a leak at any point in the system will cause these safety devices to operate so as to isolate that portion of the system and thus prevent the leakage of refrigerant from other parts of the system.

These as well as other objects and advantages will be apparent from the following description taken in connection with the accompanying drawings which form a part of the specification and on which:

Fig. l is a more or less diagrammatic view of a preferred embodiment of my invention;

Fig. 2 is a cross-sectional view of a solenoid valve used in connection with my invention;

Fig. 3 is a cross-sectional view of a one-way check valve;

Fig. 4 is a cross-sectional view of a pressurercspsnsive electric switch; and

Fig. 5 is a cross-sectional view of another type of pressure-responsive electric switch.

Referring more particularly to Fig. 1, reference character II) indicates a compressor which is opcratively connected to an electric motor II and driven thereby. A conduit I2 connects the dis- Pelham Manor, N. Y.

Appli- REISSUED charge port of compressor I3 with a suitable condenser I3 which may be cooled in any desired way, as by air or water. A conduit I4 connects the lower part of condenser I3 with a receiver I5. A conduit I6 communicates with re- 5 ceiver I5 at such a level that approximately two pounds of refrigerant may be contained in the receiver below this level. The other end of conduit I6 communicates with an auxiliary receiver 22. A conduit 23 communicates with the bottom 10 of receiver I 5. A conduit 25 connects the bottom of' the lower part of auxiliary receiver 22 with conduit 23 and is provided with a manually operable valve 26. A similar valve 21 is placed in conduit 23 between receiver I5 and the point of communication of conduit 25 therewith. A conduit 33 connects the upper part of receiver I5 with auxiliary receiver 22 and is provided with a valve 33. A float chamber 24 is placed adjacent to the lower part of receiver I5 and connected thereto by means of conduits 20 and 2I as shown. Within float chamber 24 is a float 34 pivotally 'connected to an arm 35 which is pivoted at 36.

Secured to arm 35 is a plate 31 to which is atv tached a bellows member 40. The other end of bellows 46 is secured to float chamber 24. This arrangement allows a limited movement of arm 35 about point 36, while providing a perfect seal. On the outer end of arm 35 is mounted a mercroid switch 4I arranged so that the electric circuit therethrough willbe closed when float 34 is in raised position. Secured to arm at 42 is a tension spring 43, the other end of which is secured to float chamber 24 at 44. The purpose of this spring is to tend to hold arm 35 in an extreme 35 'raised or lowered position, but when the force of this spring is overcome by float. 34 and arm 35 passes "dead center, the spring quickly snaps the arm into the opposite extreme position and thus quickly either opens or closes mercroid switch 4|. 49

Conduit 23 connects receiver I5 with solenoid valve 46, which valve is shown in detail in Fig. 2. Valve 46 comprises a housing I across which is formeda partition I42. A valve seat I43 is formed inpartition I42. A valve member I44 is slidably 45 mounted in a cylindrical member I45 and is forced downwardly to engage seat I43 by a spring I46. Valve member I44, or at least the upper part thereof, is made of magnetic material and around the outside of member I45 is placed a I magnetic coil [41. Thus, when current is supplied to coil I41 the resulting magnetic force will act to move valve member I44 upwardly against the force of spring I46 and thus open the valve. When the supply of current fails, the spring will seat valve member I44 which prevents the passage of fluid through the valve.

A conduit 41 connects the other end of valve 45 with a high side header 50. Connected to header are conduits 5|, 52, and 53. Placed in each of these conduits are check valves 54, 55, and 56, respectively. These valves are of similar construction and are shown more in detail in Fig. 3, and comprise a seat I50 upon which a valve plate I5I is arranged to be seated by gravity. Above seat I50 are a number of projections or stops I52 which limit the upward movement of plate I5I. In operation fluid tending to pass upwardly through the valve will raise plate I5I -against the action of gravity and .pass around the valve. However, fluid tending to pass in the opposite direction will force plate I5 I against seat I50 and thus the valve will be closed.

Conduits 5|, 52, and 58, which may be referred to as riser conduits, extend to the evaporators placed in refrigerator cabinets in the various apartments. The number of riser conduits depends on the number and arrangement of apartments to be served by a single system and there are here shown three riser conduits, each serving three apartments. As the apparatus connected to each'riser conduit is similar, only that 1 .connected toa single riser conduit'will be described.

Connected to riser conduit 5| are conduits 51, one for each refrigerator served by this riser.

' Placed in conduits 51 are check valves 60, similar to the valve shown in Fig. 3. Conduits 6| connect the other end of these valves to evaporators 82, which are placed in suitable refrigerator cabinets. Connected to the outlets of evaporators 52 the proper position, as to function properly the flow therethrough must be upwardly.

Similar low side headers 65 are provided for 'the return conduits "from the evaporators served by riser conduits 52 and 58, respectively. A conduit 61 is connected to low side headers 58, 85,

and 66 by branch conduits 10, 1| and 12, respectively. Ineach branch conduit is placed a solenoid valve 13, 14, and 15, respectively. These valves are all similar to the valve shown in Fig. 2. Connected to conduit 81 by means of a branch conduit 16 is a pressure-responsive switch -11, which is 'shown in detail in Fig. 5.

Switch 11 comprises a bellows contained within a housing 80a to which is connected conduit 16, so that the pressure existing within the conduit will be communicated to the bellows. Pivoted within the casing of the switch is a bell crank lever 8|, the vertical arm of which is acted upon by member 82 actuated by bellows 80. A spring tends .to move the vertical arm in a counter-clockwise direction about its fulcrum, which movement is resisted by member 82. Secured to the horizontal arm of bell crank lever 8| at 84 is a strip of resilient metal 85 which inthis switch lies flat on the horizontal arm. Secured to the other end of strip 85 is a rod 85, the other end of which is connected to a switch arm 80. In this switch strip 85 has no utility and hence might be omitted and rod 86 connected directly to lever 8|. However, this is a standard switch and in a different embodiment, to be described later, the strip is required. Arm 80 is pivoted at one end at 9| and is provided near its other end with a contact 82. Arranged below contact 82 is similar stationary contact 88. A compression spring |40"tends to force arm 80 downwardly and keep contacts 82 and 88 together. Pivoted in the easing of the switch at 84 is a catch 85, one end oi which projectsthrough an opening in the casing.

The other end of catch 85 bears against the end resisted by member 82, which is attached to bellows 80. As long as the pressure within bellows 80 is suflicient to overcome the force of spring 83, the lever will remain in the lowermost position. However, if the pressure within the bellows decreases, spring 88 will be able to move bell crank lever III, which will cause rod 86 to be moved upwardly, to the position shown, thus pivoting switch arm 80 in a clockwise direction.

This will cause contacts 82 and 83 to separate against the force of spring I40, thus opening the circuit through the switch. When lever 8| is moved to the upper position catch slips under the end of the lever, as shown, andprevents the lever being moved to its lower position. Hence, even though the pressure in bellows 80 should subsequently increase, it will be unable to re-close the switch due to catch 85, until this catch has been released by hand.

Conduit 01 communicates with a pressure-responsive switch I00 of any suitable type which is designed to open the electric circuit therethrough at a predetermined low pressure and to close the circuit at a predetermined high pressure. A conduit IOI connects switch I00 with a solenoid valve.

I04 is a pressure-responsive switch I05, shown' in detailin Fig. 4.

Switch I05 comprises a casing I06 on one side of which is mounted a bellows I01 within a housing I01a, which is connected to conduit I04. A similar bellows H0 is mounted within a housing I|0a on the other side of the casing and is likewise connected to conduit I04. Switch I05 is similar in some respects to switch 11, but embodies additional features which causes the switch to open at high pressures as well as low pressures. The additional features comprise bellows IIO which actuates a member III which in turn actuates a bell crank lever |I2 pivoted at II3. A tension spring 4 tends to rotate lever H2 in a counter-clockwise'direction. Lever H2 is connected to a snap action mechanism II5 by means of a link IIB. Mechanism'l I5 is provided with a projection I I1 arranged to strike the lower side of switcharm 80 and raise the arm and thus separate the contacts 82 and 98. A loosely mounted pin I20 projects through the back of casing I06 and is provided with a spring which tends to force it against bell crank lever II2 with the switch shown in Fig. 5, and therefore tion furnished by strip 35 between rod 06 and bell crank lever When bell crank lever H2 is moved to this position by bellows IIO, pin I20 is able to pass the ,lever and thus the lever cannot be returned to its original position by spring II4 if the pressure in bellows IIO should drop. In order to return bell crank lever I I2 to its original position and thus close the switch, it is necessary to manually pull pin I20 out, whereupon lever I I2 will return to its original position and member I20 will be held outwardly by bearing against the lever in this position.

The electric circuit for controlling the above described refrigerating system is as follows: Electric current at suitable voltage is supplied to leads I2I and I22fthrough a switch I23. Lead I22 is connected to one terminal of pressure-responsive switch I00. The. other terminal of switch I00 is connected by a conductor- I23 to one terminal of motor II. Lead I2I is connected to one terminal of switch I05, the other terminal of which is connected by means of a conductor 0 I25 with one terminal of mercroid switch M.

The other terminal of mercroid switch H is connected by conductor I24 withone terminal of switch 11, the other terminal of which is connected by means of a conductor I26 with motor II. Connected in parallel with switches 4I, I

and 11 is an electric relay I21, the windings of which have a comparatively high resistance so that .the relay will not be actuated when the circuit through the three switches is closed, but will be actuated when any one of the switches opens. The resistance of the windings of relay I21 is great enough so that sufficient current cannot pass therethrough to actuate motor II or hold any of the solenoid valves open. Relay I21 is arranged to close a circuit through an alarm bell I28 or the like whenever the relay is actuated.

Solenoid valves13, 14, 15 and I02 are connected to a circuit comprising conductors I30 and I3I. Conductor I30 is connected to conductor I26, while conductor I3I is connected to conductor I22. Thus it will be seen that current will be supplied to the circuit comprisingconductors I30 and I3I regardless of whether or not switch I00 is open or closed, but current will not be supplied to this circuit if switches 4I, I05, 11 or any one of them is open. Solenoid valve'46. on the other hand, is connected by conductors I29 and I30 to conductors I23 and I26, respectively, and hence this valve is closed whenever any one of switches 4|, I05, 11 or I00 is open.

The operation of the refrigerating system as a whole is as follows: Assume that methyl-chloride, ora similar fluid is the refrigerant employed. The system is charged with this refrigerant and approximately two pounds are contained in receiver I5. Anything in excess thereof will pass through conduit I6 into auxiliary receiver 22. In operation, valve 21 is open, valve 26 is closed and valve 33 is open. The vaporous refrigerant is compressed by compressor I0 and passes through conduit I2 to condenser I3, where it is liquefied due to cooling action. The liquid refrigerant passes through conduit I4 to receiver I5 and from the receiver through conduit 23 valve 46 and thence through conduit 41 to header 50. From header 50 11' quid refrigerant passes through riser conduits 5I, 52, and 53, and check valves 54, 55, and 56, respectively, to the various evaporators. Following the liquid through the evaporators served by riser 5I, it passes through conduits 51, chmk valves 60, and conduits 6I to the evaporators 62 of this section. In the evaporators the pressure of the liquid refrigerant is reduced. by passing through a suitable valve. The lower pressure in the evaporators causes the refrigerant to evaporate. This evaporation requires heat, which is absorbed from the contents of the interior of the refrigerator cabinet within which evaporators 62 are placed. The vaporous refrigerant thus produced in evaporators 62 passes therefrom through conduits 63 and check valves 64 to header 68;

' I03, to compressor I0, thus completing its cycle.

1e refrigerant supplFed to risers 52 and 53 passes through the evaporators supplied by these risers and returns to headers 65 and 66, respectively,

and thence passes through conduits H and 12, re-

spectively and valves 14 and 15, respectively, to conduit 61.

The temperature maintained in the evaporators is a function of the pressure existing therein. The lower the pressure, the lower the corresponding temperature. Hence, this pressure may be utilized to control the operation of the compressor and thus the desired temperature maintained in the evaporators. For this purpose pressure-responsive switch I00 is provided and, for methyl-chloride, is adjusted to open the electric circuit and thus stop motor II', and close valve 45 when the pressure has been reduced to between six and ten pounds in the evaporators 62, and to close the circuit and start mortor II and open valve 46 when the pressure in the evaporators has increased to approximately twenty pounds. Valve 46 is closed each time the motor is stopped in order to prevent surging in the system. Surging would occur if several evaporator valves happened to be open, when the compressor stops as under these conditions no refrigerant is being supplied to receiver I5 but the receiver would continue to supply refrigerant to the evaporators the valves of which are open, if valve 46 were not closed. If such surging was permittedya much larger receiver would be required to contain enough refrigerant to take care of the surge and hence a larger quantity of refrigerant would be present to escape in case of a leak.

Assume now that a leak occurs at the point marked A? ,in conduit 5|. This leak will allow liquid refrigerant contained in receiver I5, conduit 23, float,chamber 24, conduits 45 and 41, header 50 and conduit 5I to start to escape. The contents of the other risers 52 and 53 cannot reach this leak'due to the check valves 55 and 5 6,

which prevent flow from the risers into header frigerant will escape from receiver I and-float chamber 24 to allow float 34 to drop and open switch 4| before the pressure is reduced sufliciently to actuate switch I05. The opening of switch 4| or I05 will openthe circuit comprised of conductors I30 and I3I, which will cause solenoid valve 46 to close, thus isolating the leak between valve 46 and check valves 60. This will occur before a suflicient quantity of refrigerant has escaped to be injuriousto persons occupying the apartment in which the leak occurs. The opening of switch I05 or 4I will also open the motor circuit and stop the compressor and alsocause bell I28 to ring, which will give immediate warning of the leak.

.Next assume a leak to occur in one of the return conduits, for instance, conduit 63 at B. The pressure within this conduit is between six and twenty pounds gauge, wherefore vaporous refrigerant will escape through the leak. Leakage at this point will continue at a comparatively slow rate until sufficient refrigerant has leaked from the system to either reduce the pressure obtaining in the high side sufiiciently to open switch I05, as occurred in the previous case, or to reduce the quantity'of liquid refrigerant in the high side sufliciently to allow float 34 to drop and thus open mercroid switch 4l Either or both of these switches will open before a dangerous amount has escaped at B. Upon the opening of either of these switches the motor will be stopped and solenoid valves 46, 13, II, I2 and I02 will be closed. The leak will thus be isolated between valve 46 and check valve 64 in conduit 63. Check valve 64 will prevent the passage upwardly through conduit 63 of refrigerant in header 68 and of refrigerant supplied to the header by the other return conduits 63. Likewise, in this case, the bell I28 will ring as soon as either switch II or I05 is opened and thus give warning that a leak has occurred.

Next assume a leak to occur at C in conduit 61. If methyl-chloride is the refrigerant employed, the pressure within conduit 61 will be between six and twenty pounds and will, of course, drop to zero pounds gauge when the leak occurs. This will immediately cause pressure responsive switch 11 to open, as this switch is ad- J'usted to open at a, pressure just above zero pounds gauge, say, approximately, at one pound. The opening of switch 11 will open the motorcircuit, thus stopping the motor, and will also open the circuit comprised of conductors I30 and I3I, which will cause the solenoid valves to close. The leak at C" will then be isolated betweensolenoid valves I3, I4, I5 and I02, and the amount of refrigerant which will have escaped will be negligible. The opening of switch I1 will cause bell I28 to give warning of the leak.

Switch I05 is arranged to open upon the occurrence of an abnormal pressure in the high side as well as in case of a subnormal pressure so that a dangerously high pressure may not be built up therein. Such a pressure might result from several causes, such as the failure of valve 46 to open when the motor starts or a failure of cooling water in case the condenser'is water cooled. 1

Excess refrigerant placed in a system when initially charged will pass through conduit l6 to auxiliary receiver 22, where it will remain as it cannot flow back into circulation as long as valve 26 is closed. The provision of auxiliary receiver 22 prevents an excessive quantity of refrigerant being present in the receiver I5 of the -pressor, a condenser, evaporation means, .001!- system and thus maintains at a minimum the amount of refrigerant that may escape from a leak. Due to'the small quantity of refrigerant present in receiver I5, a leak will cause the high side pressure to drop rapidly and thus cause switch I05 to open and of course float chamber 24 will become emptied much sooner with a small quantity of liquid in the receiver I5 than it would if a larger quantity were present. In case a leak occurs and is repaired, any excess refrigerant in auxiliary receiver 22 may be introduced directly into the receiver I5 to make up for refrigerant lost through the leak by a proper manipulation of the manually operable valves. To do this, valve 26 should be opened and valve 2'! closed. Liquid refrigerant contained in receiver 22 will then pass through conduit 25 into conduit 23. When all of the liquid refrigerant has been thus forced out of auxiliary receiver 22, the valves are re- I turned to their former position and liquid re 20 frigerant supplied from receiver I5 through conduit 23, Valve 26 may be provided with a lock so that it may be opened and refrigerant introduced into the circulating system only by a duly authorized person.

I have shown and described a system employing pressure control 01' the compressor. With such control I prefer'the use of'float valves for regulating the supply of liquid refrigerant to the evaporators. My safety system is equally applicable to other regulation combinations and is independent of the normal control of the refrigerating system. My safety arrangements may be used on a system employing pressure operated expansion valves to control the supply of refrigerant to the evaporators or expansion valves operated by a plurality of impulse sources. With expansion valves of the last mentioned types, thermostatic .control of the motor may be used instead of pressure control.

While I have shown a more or lessspecific embodiment of my invention, it is to be understood that this has been done for purposes of illustration and that the invention is not limited thereto. It will be evident that parts of the system which I have shown may be used separately. Other refrigerants than those described may be employed and their use in combination with such a system falls within the scope of the invention, which is to be limited by the appended claims viewed in the light of the prior art.

What I claim is:

1. A refrigerating system comprising a compressor, a condenser, evaporation means, conduits connecting said compressor, condenser and evaporation means and automatic mean: for divi-ding said system into isolated sections operable upon the occurrence of abnormal change in pressure at any point in the system.

2. A refrigerating system comprising a coinpressor, a condenser, evaporation means, canduits connecting said compressor, condenser and evaporation means, valves in said conduits and pressure-responsive means operable upon themduction of pressure within said system resulting from a leak in said system for closing said valves to divide said system into isolated sections.

3. A refrigerating system comprising a com-,

duits connecting said compressor, condenser and evaporation means, valves in said conduits and liquid level responsive means operable upon the reduction of the quantity of liquid refrigerant contained within said system resulting from a crease of pressure within said system for closing said valves to divide said system into isolated sections.

5. A refrigerating system comprising a compressor, a condenser, an evaporator, means including a conduit for supplying said evaporator with liquid refrigerant from said condenser, a one-way valve in said conduit adjacent said evaporator, means for conveying vaporous refrigerant from said evaporator to said compressor, a

second valve in said conduit and means for closing said second valve when the pressure in said conduit is below normal.

6. A refrigerating apparatus comprising a compressor, a, condenser, a receiver, an evaporator, means including a conduit for supplying said evaporator with liquid refrigerant from said receiver, a one-way valve in said conduit adjacent said evaporator, means for conveying vaporous refrigerant from said evaporator to said compressor, an electrically actuated valve in said conduit and means including a float operated switch responsive to the liquid level in said receiver for closing said valve.

7. A refrigerating apparatus comprising a compressor, a condenser, evaporation means, means including a first conduit for supplying said evaporation means with liquid refrigerant from said condenser, means including a second conduit for conveying vaporous refrigerant from said evaporation means to said compressor, an electrically actuated valve in each of said conduits and means including a pressure responsive switch for closing said valves when the pressure in said first conduit is below normal.

8. A refrigerating apparatus comprising a compressor, a condenser, evaporation means, means including a first conduit for supplying said evaporation means with liquid refrigerant from said condenser, means including a second conduit for conveying vaporousrefrigerant from said evaporation means to said compressor, an electrically actuated valve in each of said conduits and means including a pressure responsive switch for closing said valves when the pressure in said first conduit is above normal.

9. A refrigerating apparatus comprising. a compressor, a condenser, evaporation means, means including a first conduit for supplying said evaporation means with liquid refrigerant from said condenser, means including a. second conduit for conveying vaporous refrigerant from said evaporation means to said compressor, an electrically actuated valve in each of saidconduits and means including a pressure responsive switch for closing said valves when the pressure in said first conduit is other than normal.

10. A refrigerating apparatus comprising a compressor, a condenser, evaporation means, means including a first conduit for supplying said evaporation means with liquid'refrigerant from said condenser, means including a second conduit for conveying vaporous refrigerant from said evaporation means to said c'ompressor, an electrically actuated valve in each of said conduits and means including a pressure responsive switch for closing said valves when the pressure in said second conduit is below normal.

11. A refrigerating apparatus comprising a compressor, a condenser, a receiver, evaporation means, means including a first conduit for supplying said evaporation means with liquid refrigerant from said receiver, means including a second conduit for conveying vaporous refrigerant from said evaporation means to said com-,- pressor, an electrically actuated valve in each of said conduits and means including a float operated switch responsive to liquid conditions in said receiver for closing said valves.

12. A refrigerating apparatus comprising a compressor, a condenser, a receiver, an auxiliary receiver, an evaporator, conduits connecting said compressor with said condenser, said condenser with said receiver, said receiver with said evaporator and said evaporator with said compressor, a conduit connecting said receiverwith said auxiliary receiver and means to regulate fiow of fluid through said lastmentioned conduit so as to limit the quantity of liquid in said receiver.

13. A refrigerating system comprising a compressor, a condenser, a receiver, an auxiliary receiver, evaporation means, conduits connecting said compressor with said condenser, said condenser with said receiver, said receiver with said evaporation means and said evaporation means with said compressor, a conduit connecting said receiver with said auxiliary receiver, means to regulate flow of fluid through said last mentioned conduit so as to limit the quantity of liquid in said receiver, electrically actuated valves for dividing said system into isolated sections and means including a float-operated switch responsive to liquid conditions in said receiver for clos- 85 ing said valves.

14. A refrigerating system comprising a com pressor, a condenser, a receiver, an auxiliary receiver, evaporation means, conduits connecting said compressor with said condenser, said condenser with said receiver, said receiver with said evaporation means and said evaporation means with said compressor, a conduit connecting said receiver with said auxiliary receiver, means to regulate'fiow of fluid through said last mentioned conduit so as to limit the quantity of liquid in said receiver, electrically actuated valves for dividing said system into isolated sections and means including a pressure responsive switch for closing said-valves when the pressure in said receiver is below normal.

15. A refrigerating system comprising a compressor, a condenser, a plurality of evaporators, a low sideheader, means comprising a conduit and branch conduits connecting said condenser with said evaporators, a one-way valve in each of said branch conduits, return conduits connecting said evaporators with said low side header, a one-way valve in each of said return conduits, a magnetically actuated valve in-said first o mentioned conduit, a conduit connecting said low side'header with said compressor, a magnetically actuated valve in said last mentioned conduit and means comprising a pressure responsive switch for closing said magnetically ac- 5 tuated valves when a subnormal pressure exists in said system,

16. A refrigerating system comprising a compressor, a condenser, a plurality of evaporators,

a low side header, means comprising a conduit and branch conduits connecting said condenser with said evaporators, a one-way valve in each of said branch conduits, return conduits connecting said evaporators with said low side heade er. a one-way valve in each of said return conduits, a magnetically actuated valve in said first mentioned conduit, a conduit connecting said low' side header with said compressor, a magnetically actuated valve in said last mentioned conduit and means comprising a pressure responsive switch for closing said magnetically actuated valves when a pressure above normal exists in said system.

1'7. A refrigerating system comprising a compressor, a condenser, a receiver, a plurality of evaporators, a low side header, means comprising a conduit and branch conduits connecting said condenser with said evaporators, a one-way valve in each of said branch conduits, return conduits connecting said evaporators with said low side header, a one-way valve in each of said return conduits, a magnetically actuated valve in said flrst.mentioned conduit, a conduit connecting said low side header with said compressor, a magnetically actuated valve in said last mentioned conduit and means comprising a float actuated switch responsive to liquid conditions in said receiver for closing said valve.

18. A refrigerating system comprising a compressor, a condenser, a high side header, a plurality of evaporators, a plurality of low side headers, a conduit connecting said condenser with said high side header, a magnetically actuated valve in said conduit, means comprising a plurality of riser conduits each connected with a plurality of branch conduits for connecting said high side header with said evaporators, a one-way valve in each of said riser conduits, a one-way valve in each of said branch conduits, a plurality of return conduits connecting said evaporator with said low side headers, one-way valves in each of said return conduits, means comprising a main return conduit and branch conduits connecting said low side headers with said compressor, a magnetically actuated valve in said main return conduit and in each of said last mentioned branch conduits, and means comprisinga pressure responsive switch for closing.

all the aforesaid magnetically actuated valves when a subnormal pressure exists in said system.

19. A refrigerating system comprising a compressor, a condenser, a high side header, a plurality of evaporators, a plurality of low side headers, a conduit connecting said condenser with said high side headers, a magnetically actuated valve in said conduit, means comprising a plurality of riser conduits each connected with a plurality of branch conduits for connecting said high side header with said evaporators, a one way valve in each of said riser conduits, a one-way valve in each of said branch conduits, a plurality of return conduits connectingsaid evaporators with said low side headers, one-way valves in each of said return conduits, means comprising a main return conduit and branch' conduits connecting said low side headers with said compressor, a magnetically actuated valve in said main return conduit and in each of said last mentioned branch conduits, and means comprising a pressure responsive switch for closing all the aforesaid magnetically actuated valves when a pressure greater than normal exists in said system. a J l l 20. A refrigerating system comprising a compressor, a condenser, a receiver, a high side header, a plurality of evaporators, a plurality of low side headers, a conduit connecting said condenser with said high side headers, a magnetically actuated valve in said conduit, means comprising a plurality of riser conduits each connected with a plurality of branch conduits for connecting said highside header with said evaporators, a one-way valve in each of said riser conduits, a one-way valve in each of said branch conduits, a plurality of return conduits connecting said evaporators with said low side headers, one-way valves in each of said return conduits, means comprising a main return conduit and branch conduits connecting said low side headers with said compressor, a magnetically actuated valve in said main return conduit and in each of said last mentioned branch conduits, and means comprising a float actuated switch responsive to liquid conditions in said receiver for closing all the aforesaid magnetically actuated valves.

21. A refrigerating system comprising a plurality of evaporators, means for supplying refrigerant to said evaporators, said means com,- prising a header, a plurality of'riser conduits connected to said header and a plurality of branch conduits connecting each evaporator with one of said riser conduits, a valve in each of said riser conduits for preventing flow therethrough into said header and a valve in each of said branch conduits for preventing flow therethrough into the respective riser conduits.

22. An electrically operated refrigerating system comprising a compressor, a condenser, evaporation means, conduits connecting said compressor, condenser and evaporation means, valves in said conduits, and -means for closing said valves to divide said system into isolated sections operable upon the failure of electric current for operating the system.

23.An electrically operated refrigerating system comprising a compressor; a condenser, an evaporator, means including a conduit for supplying said evaporator with liquid refrigerant from said condenser, a one-way valve in said conduit adjacent said evaporator, means for conveying vaporous refrigerant fromsaid evaporator to said compressor, a second valve in said con it and means for closing said second valve upon the failure of electric current for operating said system.

24. An electrically operated refrigerating system comprising a compressor, a condenser, 'evap-- oration means, means including a first conduit for supplying said evaporation means with liquid evaporation means with said compressor, a.

conduit connecting said receiver with said auxiliary receiver, means to regulate flow of fluid through said last mentioned conduit so as to Y limit the quantity of liquid in said receiver,

valves for dividing said system into isolated seccomprising a conduit and branch conduits connecting said condenser with said evaporators, a one-way valve in each of said branch conduits, return conduits connecting said evaporators with said low side header, a one-way valve in each of said return conduits, a magnetically actuated valve in said first mentioned conduit, a'conduit connecting said low side header with said compressor, a magnetically actuated valve in said last mentioned conduit and means for closing said magnetically actuated valves upon a failure of electric current for operating said system.

27. An electrically operated refrigerating system comprising a compressor, a condenser, a high side header, a plurality of evaporators, a plurality of low side headers, a conduit connecting said condenser with said high side header, a magnetically actuated valve in said conduit,-means comprising a plurality of riser conduits each connected with a plurality of branch conduits for connecting said high side header with said ev'aporators, a one-way valve in each of said riser conduits, a one-way valve in each of said branch conduits, a plurality of return conduits connecting said evaporator with said low side headers, one-way valves in each of said return conduits,

means comprising a main return conduit and branch conduits connecting said low side headers with said compressor, a magnetically actuated valve in said main return conduit and in each of saidlast mentioned branch conduits and means for closing all the aforesaid magnetically actuated valves upon a failure of electric current for operating said system.

28. That improvement in the art of refrigeration through the agency of an electrically operated refrigerating system which comprises producing an electromagnetic field with the electric current for operating the system and dividing the system into isolated sections upon decrease in strength of said field below a predetermined value.

29. A compressor, a condenser, and an evapo rator connected to form a refrigerating system, and automatic means for dividing the system into isolated sections operable upon a predetermined fall in liquid level in the high pressure side of the system. a

30. A compressor, a condenser, and an evaporator connected to form a refrigerating system, and automatic means for stopping the compressor and for dividing the system into isolated sections operable upon a predetermined fall of the liquid level in the high pressure side of the system.

31. A compressor, a condenser, and an evaporator connected to form a refrigerating system,

and automatic means for stopping the'compressor and for sounding a signal operable upon a predetermined fall of the liquid level in the high pressure side of the system. e

32. A compressor, a condenser, and an evaporator connected to form a refrigerating system, and automatic means for dividing the system into isolated sections and for sounding a signal operable upon a predetermined fall of the liquid level in the high pressure side of the system.

33. A compressor, a condenser, and' an evaporator connected to form a refrigerating system, electrical means for supplying power to the system, and automatic means for dividing the system into isolated sections operable upon a predetermined fall in liquid level in the high pressure side of the system. v

34. That improvement in the art of refrigeration which comprises altering an electric circuit due to a predetermined fall in liquid level in the high pressure side of the system and dividing the system into isolated sections due to the alteration of said circuit.

35. In an electrically operated refrigerating system means for producing an electromagnetic field, utilizing electric current for operating the system, means for dividing the system into isolated sections operative upon decrease in strength of said field below a predetermined value, and additional means for dividing the system. into isolated sections upon a predetermined fall of liquid level in the high pressure side of the system.

36. In a refrigerating system employin electric current" means .for automatically dividing the system into isolated sections, and means responsive to a predetermined fall of liquid level in l the high pressure side of the system for effecting said automatic division, and additional means operable upon the failure of electric current for dividing the system into isolated sections.

37. A compressor, a condenser, and an evaporator connected to form a refrigerating system, an alarm associated with said system, and automatic means for sounding said'alarm, said automatic means being adapted to be actuated upon a predetermined loss of fluid from the high pressure side of the system.

38. A compressor, a condenser, and an evaporator connected to form ,a refrigerating system, an alarm associated with said system, and automatic means for sounding said alarm, said automatic means being adapted to be actuated upon a predetermined loss of'fluid from the system.

39. The improvement in the art of refrigeration" which comprises dividing a refrigerating system into isolated sections in response'to a predetermined alteration of an electrical circuit,

forming a partof the system.

40. A refrigerating system including condensing and evaporating means connected in series, and'means adapted to operate upon the occurrence of a leak in any portion of said system to subdivide the system into a number of isolated sections.

41. A refrigerating system comprising interconnected compressing, condensing and evaporating means, valves in said system, and means adapted to operate saidv valves upon the occurrence of a leak in any portion of said system for subdividing said system into a plurality of independently isolated sections whereby said leak will only permit the escape of refrigerant from the respective isolated section.

42. A refrigerating system comprising interconnected compressing, condensing. and evaporating means,'valves in said system, and means adapted to operate said valves responsive to a predetermined 'loss of fiuid from said system for subdividing the system into a plurality of independently isolated sections.

43. A refrigerating system comprising interconnected compressing, condensing and evaporating means, valves in said system, and means adapted to operate said valves responsive to either a predetermined loss of fluid from the system or in response to an abnormal drop in pressure resulting from a leak in the system for subdividing said system into a plurality of inchange of liquid level for subdividing said system into a plurality of independent isolated sections.

45. A refrigerating system comprising evapo- 5 rating, condensing and other interconnected elev ments, valves in said system, and means adapted to operate said valves to subdivide said sistem into a plurality of independent sections and operable subject to any one of a number of conditions including loss of fluid, abnormal pressure change or abnormal liquid level change.

EDWARD T. WILLIAMS. 

